Field of the Invention
This invention relates to electrical connectors. More particularly, this invention relates to a device for forming electrical connections between at least one pair of electrical conductors. The device contains one member of each conductor pair residing in individual passages. When the connector is joined with a mating connector the members of each pair of conductors are joined to complete the electrical circuit(s). The present connector provides a means for preventing entry of water vapor and other contaminants into the area occupied by the junctions between conductor pairs, irrespective of the number of conductor pairs being joined.
One method for sealing the area occupied by the junctions of conductor pairs in an electrical connector is by passing the conductors through a perforated gasket. The holes in the gasket are aligned with the passages of the connector shell containing the electrical conductors. The contour of the gasket conforms to the contour of the connector shell, and forms a seal when the mating sections of two connectors are joined.
To maximize production efficiency it is often desirable to fabricate a single connector for a variety of applications, some of which utilize fewer than the maximum number of conductors accommodated by the passages in the connector, thereby leaving some of the passages vacant.
It should be apparent that if any passages in the connectors do not contain conductors, the corresponding unoccupied holes in the gasket create the potential for gaps in the seal, allowing moisture and other contaminants to reach the area of the junctions between conductor pairs and adversely affect the mechanical and electrical properties of these junctions.
In the past, vacant passages in connectors containing perforated gaskets as sealing means have been filled with pins formed from an electrically insulating material. The contour of the pins corresponds to the contour of the passages. The disadvantage of this method is the cost of fabricating the insulating pins and inserting them in the unused passages of the connectors.
Penetrable, repairable gel type organosiloxane compositions have been used on the inner surface of electrical connectors in place of rubber gaskets to form seals around the electrical conductors. The cured gel is sufficiently flowable that it forms a seal around the conductor. A disadvantage of replacing a gasket with a cured gel in this application is the absence of sufficient cohesive strength and adhesion between the gel and the inner surface of the connector to avoid displacement of the gel, with accompanying loss of sealing action, in the presence of superatmospheric pressure applied through the unoccupied passages of the connector.
U.S. Pat. No. 3,989,338, which issued to Gosser on Nov. 2, 1976 describes a connector intended for the manual insertion of electrically conductive terminal pins in predetermined passages identified by numbers. The inventive feature of the connector is to increase the legibility of the numbers identifying the various passages by having the number appear on a layer of penetrable material that is adhered to the surface containing the holes.
The types of material from which the overlying layer can be formed and the nature of the adhesive are not described.